The Value Of DWI Combined With MT In Detecting The Activity Of Sacroiliac Joint Lesions In Ankylosing Spondyliti

Purpose: Diffusion weighted imaging(DWI)is sensitive to bone marrow edema,which can reflect whether ankylosing spondylitis is active or not.The purpose of this study was to evaluate the reproducibility of DWI in the identification of sacroiliac joint lesions in active and inactive ankylosing spondylitis.Materials and methods: The MRI and clinical data of 39 patients with ankylost spondylitis diagnosed by rheumatologists in our hospital from April 2018 to November2018 were retrospectively analyzed,and the lesions were divided into bone marrow edema(BME),sclerosis,fat deposit,and normal bone marrow,they are described as ADC(BME),ADC(SME),ADC(FAT deposit),and ADC(NABM),respectively.According to BASDAI,ESR and CRP,the patients were divided into active group(n = 26)and inactive group(n =13).It were measured twice(1 day apart)by radiologist with 7 years of service and twice(1 week apart)by radiologist s with 10 years of service.Intra-observer and inter-observer reproducibility were analyzed by coefficient of variation(CV),intraclass correlation coefficient(ICC)and Bland-Alatman method.Independent sample t test was used to evaluate whether there were differences in ADC,general data and clinical activity indicators in each lesion area between the active and inactive groups.The differences in ADC measurements were analyzed by paired sample t test.Results: The repeatability of ADC(BME)was excellent with CV less than 10%(5.94).The repeatability of ADC(Sclerosis)and ADC(NABM)was good with CV of 10.74% and17.36%,respectively.CV value of ADC(fat deposit)is 20.23%,with acceptable repeatability.The ICC values of ADC(BME)in the active group and inactive group were0.984 and 0.926 between observers,and the reproducibility level was very good.For ADC(sclerosis)of active group,ADC(fat deposit)and ADC(NABM)of inactive group,the reproducibility level of was very good(0.885,0.913,0.811).For ADC(fat deposit)of active group,ADC(NABM)and ADC(Sclerosis)of inactive group,the reproducibility level was good(0.722,0.792,0.755).There was no statistical significance in ADC(BME),ADC(fat deposit)and ADC(NABM)between the two measurements(all P > 0.05).The ADC values of edema and sclerosis in the active group were both higher than those in the inactive group,with statistical significance(P < 0.05).The ADC(NABM)of the active group was lower than that of the inactive group,and the difference was statistically significant(P < 0.05).There was no statistical difference in ADC values between the active group and the inactive group.Conclusions: DWI can detect bone marrow edema,fat deposition and sclerotic lesions of the sacroiliac joint.This technique is easy to detect lesions in the bone marrow edema area with excellent repeatability,and have good repeatability in the judgment and measurement of normal control area and sclerotic lesions.However,the judgment value of DWI for fatty deposition lesions needs further study.Purpose: Magnetization transfer(MT)can enhance the contrast of different tissues.Magnetization transfer effect of hyalurontium is obvious in the cartilaginous components of the sacroiliac joint.The purpose of this study was to evaluate the reproducibility of MT in the identification of sacroiliac joint lesions in active and inactive ankylosing spondylitis.Materials and methods:From April 2018 to November 2018,3.0T GE Magenetic Resonance(MR)scanner was applied to 39 patients(According to BASDAI,ESR and CRP,the patients were divided into active group(n = 26)and inactive group(n = 13))with ankylost spondylitis(radiological grade below 2)and 38 control patients underwent MT scan(MT frequency compensation:12200Hz,MT Pulse Type:Exerted saturated Fermi),respectively in the pulse acquisition twice before and after images,noexerted saturation pulse exerted saturation(M0)and the pulse image after image(Ms),measured M0 and Ms image before the sacroiliac joint in lower ventral signal intensity of articular cartilage.All ROI were measured by 7 years working fixed number of year of doctors twice(2 times interval.1 day)and twice(1 week apart)by physicians with 10 years of service.Magnetic transfer rate of cartilige(MTRc)was calculated by the formula.General data and clinical activity indexes of the patient group and the control group were collected.The differences of MTRc,general data and clinical activity indexes between active group,inactive group and control group were compared by one-way analysis of variance.Statistical differences in MTRc were compared by paired t test.Intraclass correlation coefficient(ICC)analysis,coefficient of variation(CV)and Bland-Alatman method were used for intra-observer and inter-observer reproducibility analysis.Results: The reproducibility of MTRc in the inactive group and the control group was good(CV=11.70%,18.18%),and the reproducibility of MTRc in the active group was acceptable(CV=23.94%).The reproducibility level of the inactive group and the control group were very good,ICC were 0.892 and 0.819,respectively.ICC=0.639 in the activity group,and the repeatability level were moderate.MTRc values measured twice in the activity group were lower than those in the control group(P < 0.001).MTRc values measured twice in the active group were lower than those in the inactive group(P < 0.001).MTRc measured twice in the inactive group was lower than that in the control group,andthe difference in MTRc was not statistically significant(P > 0.05).Conclusions: Preliminary results showed that the MTRc of sacroiliac articular cartilage was lower in patients with ankylosing spondylitis below radiological grade 2 than in control group.It is feasible for MT to be used to detect sacroiliac articular cartilage lesions in patients with ankylost spondylitis below radiological grade 2,among which MTRc rerepeatability of inactive group and control group was excellent,and rerepeatability of active group was moderate.Purpose: This study evaluated the value of DWI in detection activity preliminarily,ADC and MTRc as the quantitative indicators in the activity of sacroiliac joint lesions in ankylosing were compared,as well as the correlation between the clinical inflammation indicators.Materials and methods:DWI and MT images of 77 patients with clinically diagnosed AS with radiological grade below 2 from December 2018 to December 2020 were selected(According to BASDAI,ESR and CRP,the patients were divided into active group(n = 26)and inactive group(n = 13)):The apparent diffusion coefficient(ADC)of bone marrow edema area,sclerosis area,fat deposition area and normal bone marrow area were measured,and the magnetic transfer rate(MTR)of cartilage of each sacroiliac joint was calculated.Mean values and standard deviations of ADC and MTRc were calculated.Independent sample t test was used to compare the differences between the active group and the inactive group in ADC(BME),ADC(Sclerosis),ADC(Fat deposit),ADC(NABM)and MTRc of the sacroiliac joint cartilage.ROC curve was used to analyze the efficacy of each parameter in diagnosing the activity of ankylosing spondylitis sacroiliac arthritis.Parameters with predictive value were combined through regression analysis,and the predictive value of each parameter combined with a single indicator for the activity of ankylosing spondylitis sacroiliac arthritis was further compared through ROC curve.Results: The ADC(BME)of the active group was significantly higher than that of the inactive group(P < 0.001).ADC(NABM)in the active group was lower than that in the inactive group(P < 0.01).There was no significant difference in ADC(Sclerosis)and ADC(Fat deposit)in fat deposition area(P > 0.05).The difference in MTRc between the active and inactive groups was statistically significant(P = 0.001).AUC of ADC(BME),ADC(NABM)and MTRc were 0.773,0.793 and 0.748,respectively,all P < 0.05.The specificity of ADC(Fat deposit)was the highest(82.35),the specificity of MTRc was the lowest(64.71),the sensitivity of MTRc and ADC(BME)was the highest(88.37),and the sensitivity of ADC(Fat deposit)was the lowest(53.49).After logistic regression combination,the AUC of ADC(BME)_ADC(NABM),ADC(NABM)_MTRc and ADC(BME)_MTRc were 0.845,0.838 and 0.849,respectively,and there was nosignificant difference among them.The AUC of the combined index was higher than that of the single index before the combined index.Conclusions: Bone marrow edema accompanied by decreased magnetic transfer of sacroiliac articular cartilage is helpful for the detection of active sacroiliac arthritis lesions.The combined index of ADC value and MTRc was better than single index in diagnosing the activity of ankylosing spondylitis.Purpose: Diffusion weighted imaging(DWI)has reached a consensus on the judgment of the activity of sacroiliac arthritis,while magnetic transfer contrast imaging(MT)has rarely been reported on the judgment of the activity of sacroiliac arthritis.This study preliminarily evaluated the value of DWI and MT quantitative indicators ADC and MTR in the detection of sacroiliac joint disease activity in ankylosing spondylitis,and compared the activity value with clinical indicators and analyzed the correlation.Materials and methods: General data(age,sex,course of disease,age of onset,human leukocyte antigen)of 61 patients with ankylosing spondylitis(radiological grade below 2)from April 2019 to March 2020 were selected.HLA)-B27,laboratory test results(C-reactive protein(CRP),erythrocyte sedimentation rate,ESR),BASDAI,Patient Global Assessment(Pa GA),Physician Global Assessment(Py GA),According to the above data,the ASDAS-CRP(ASDAS based on CRP calculation)and ASDAS-ESR(ASDAS based on ESR calculation)are calculated.DWI and MT images of 61 patients with AS were analyzed,quantitative indexes ADC(BME,Sclerosis,Fat deposit,and NABM)were measured,and magnetic susceptibility(MTRc)of sacroiliac articular cartilage was calculated.Patients were divided into high disease activity group and low disease activity group according to Pa GA,Py GA and BASDAI+ESR+CRP respectively.The independent sample t test was used to compare the differences of quantitative indicators(ADC and MTRc)between groups.Multiple linear regression was used to compare the predictive value of clinical activity index and quantitative index(ADC,MTRc)on disease activity and their correlation,and to compare the area under ROC curve(AUC)of trial subjects.Results: When judging disease activity according to PYGA score,there were significant statistical differences in Basdai,CRP,ASDAS-CRP,ASDAS-ESR,MTRC,ADC(NABM)and ADC(BME)between high disease activity group and low disease activity group(P < 0.05).When disease activity was judged by PAGA score,there were statistical differences in ESR,ASDAS-ESR and ADC(NABM)between the high disease activity group and the low disease activity group(P < 0.05).When evaluating disease activity according toBas DAI +ESR+CRP score,there were statistically significant differences in Bas DAI,CRP,ASDAS-CRP,ASDAS-ESR,PYGA,PAGA,MTRC,ADC(NABM)and ADC(BME)(all P < 0.05).BASDAI,ASDAS-CRP,and ASDAS-ESR were correlated with disease activity according to PYGA or PAGA(P < 0.05),while PYGA,CRP,ASDAS-CRP,and ASDAS-ESR were moderately correlated with disease activity according to BASDAI+ESR+CRP.BASDAS,MTRc,ADC(BME)and CRP could predict disease activity(R2 =0.423,F=11.974,P=0.000)when Py GA score was used to determine disease activity.ASDAS-ESR,ESR and BASADI could predict disease activity(R2 =0.412,F=14.991,P=0.000).when Pa GA score was used to determine disease activity.ASDAS-CRP and Py GA could predict disease activity(R2 =0.531,F=35.033,P=0.000)when disease activity was judged according to BASDAI +ESR+CRP.When Py GA was used to predict disease activity,the AUC(Area Under Curves)of BASDAI,MTRc,ADC(BME)and CRP were 0.878,0.750,0.713 and 0.728,respectively.When predicting disease activity according to Pa GA,the AUC of BASDAI,ESR and ASDAS-ESR were 0.743,0.580 and 0.711,respectively.When disease activity was judged according to BASDAI+ESR+CRP,the AUC of ASDAS-CRP and Py GA were 0.900 and 0.911,respectively.Conclusions: BASDAI,MTRc,ADC(BME)and CRP can predict activity when grouped according to Py GA score.Taking BASDAI as an example(which can predict activity when grouped according to Py GA score),AUC of BASDAI is higher than that of Pa GA score when grouped according to Py GA.Compared with Pa GA grouping,patients with Py GA grouping could be evaluated by doctors based on clinical symptoms,laboratory examination and imaging data.However,when assessing disease activity according to BASDAI+ESR+CRP,the AUC,sensitivity and specificity of ASDAS-CRP and Py GA were higher than those entered into the equation by other grouping methods.Purpose: To evaluate the value of fat quantitative by iterative decomposition of water and fat with echo asymmetry and least square estimation-iron quantification(IDEAL-IQ)in the sacroiliac arthritis of healthy volunteers and AS patients.Materials and methods: This was a prospective study.Between April 2019 to March 2020 were selected,sixty healthy volunteers at the Xiyuan Hospital of the China Academy of Chinese Medical Sciences were recorded.They were divided by age(15-30 years group,31-50 years group,51~years group),gender(male,female)and body mass index(BMI)(>18.5,18.5-23.9,>24.0)for three and two groups,respectively.Thirty-nine AS patients were divided into active group(n = 26)and inactive group(n = 13).Fat fraction of iliac-side(Fi)and sacral-side(Fs)were obtained for all groups.Multivariate analysis of variance was used to analyze the effects of gender,age and BMI groups on Fi and Fs.Independent sample t test and Paired sample t test and one-way ANOVA were used to compare the differences between Fi and Fs.The value of Fi and Fs in predicting the activity of AS sacroiliac arthritis was analyzed by ROC.Results: Fi and Fs were statistically significant in both 31-50 years group and 51-years group(P = 0.006,P=0.028)and between males and females in over 51 years old group(P=0.009,0.004).There was no significant difference in BMI mean value between the three groups(F = 0.717,P = 0.493).Variance analysis of three factor and double factors analysis showed that the interaction between gender,age groups and BMI grade had no statistical significance on both Fi and Fs(three factors :F(2,45)=1.538,P=0.226),double factor: gender and age group,gender and BMI group,age group and BMI group),all P value >0.05,).Both Fi and Fs have all been influenced by age(F = 4.252,P = 0.019,partial η2 = 0.136;F = 12.694,P < 0.001,partial η2 = 0.320)respectively.Fs has been influenced by gender(F = 9.007,P = 0.004,partial η2 = 0.143).There were no significant differences in body weight,height and BMI between active and inactive groups(P > 0.05).Fi of active group and inactive group,male and female patients,Fs of active group and inactive group,male and female patients showed no statistical difference(P > 0.05).There were statistically significant differences between Fi and Fs in the active group and Fi and Fs in the inactive group(P < 0.05).According to ROC curve analysis,the AUC,sensitivity and specificity of Fi were 0.624,88.5 and 38.5 respectively,while the AUC,sensitivity and specificity of Fs were 0.547,42.3 and 76.9 respectively.Conclusions:: IDEAL-IQ sequence can be used to quantitatively assess sacroiliac joint fat content in healthy volunteers.The FF value of sacroiliac joint can predict the activity of AS sacroiliac arthritis to some degree.